Plastics have a wide use and there are many types of industries from liquid containers to fibres. Many of the products are used in the fast moving consumer industry and require colour for visual presentation.
It is the masterbatch industry that supplies the colour additives to the plastic industry and the pigment is commonly suspended in a polymer. Masterbatch manufacturers use high speed mixers or internal mixers to first mix the pigment and this is then fed through an extruder with high temperatures and high pressures to combine the pigments and the carrier and to form a granule.
The ideal properties of the pigment are for a high dispersion in the base material, common problems are that the pigment or other materials are subject to high temperatures as well as high pressures to combine them, as well as high sheet in the initial stages, this leads to degradation of the material as well as reagromalation of the pigment.
Dispersion is therefore reduced due to the non-uniform particle size in the material i.e., a mix with a one micron particle size ends up with a percentage of higher micro particles, thus affecting the final distribution. The final colour, tint strength are affected by these various processes.